Mercedes Benz is also under investigation. State media said regulators visited the company's offices in Shanghai earlier this week.

The authorities are also reported to be looking into the activities of 12 Japanese auto parts companies.

A spokesman for Daimler(DDAIF), which owns Mercedes, said the company was assisting authorities in their investigation. Audi, owned by Volkswagen(VLKAF), confirmed that an investigation was underway, but a spokeswoman said the company would not be able to comment further until it was over.

Chrysler parent Fiat(FIADF) did not immediately respond to a request for comment.

Foreign automakers have found China to be a massively important new market. The appetite for new cars -- especially luxury models -- has helped bolster the bottom line of companies facing weak demand in Europe and the United States.

Chinese authorities said last month that they're investigating Microsoft(MSFT, Tech30) for possible violations. The government said the company had not fully disclosed information related to its Windows and Office systems.

Qualcomm(QCOM, Tech30) has also been targeted in a similar probe. The company said China was looking into the company's licensing business, and that the investigation had hurt revenues.